Extremely poor service

My Dad bought my lil brother a phone with his account in March and the phone froze and didnt work about 3 weeks after it was purchsed,he took it back and they booked for it for repairs,it went and came back unfixed and they said they sending it back again,its been 3months now that my lil brother is without a phone,cant they replace it,I mean this is such an inconvinience,my dads ID no is *** his initials and surname is BR Moteme,we will go to the ombudsman if we dont get any feedback regarding this as we have been following up forever now and no one is taking responsibilty to get this query sorted up.Daddy currently doesnt have a phone so they can contact me on *** or ***